U.S. patent application number 14/410634 was filed with the patent office on 2015-12-24 for vehicular latch with direct locking of pawl.
This patent application is currently assigned to Magna Closures Inc.. The applicant listed for this patent is Magna Closures Inc.. Invention is credited to Kris Tomaszewski.
Application Number | 20150368934 14/410634 |
Document ID | / |
Family ID | 49781985 |
Filed Date | 2015-12-24 |
United States Patent
Application |
20150368934 |
Kind Code |
A1 |
Tomaszewski; Kris |
December 24, 2015 |
VEHICULAR LATCH WITH DIRECT LOCKING OF PAWL
Abstract
In one aspect a vehicle latch is provided having a ratchet, a
primary pawl, an auxiliary ratchet and a secondary pawl, and
further including a gear that is movable to a secondary pawl
locking position wherein the gear directly blocks movement of the
secondary pawl and locks the secondary pawl in an auxiliary ratchet
holding position to prevent premature or unintended opening of the
latch.
Inventors: |
Tomaszewski; Kris;
(Newmarket, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Magna Closures Inc. |
Newmarket |
|
CA |
|
|
Assignee: |
Magna Closures Inc.
Newmarket
CA
|
Family ID: |
49781985 |
Appl. No.: |
14/410634 |
Filed: |
June 17, 2013 |
PCT Filed: |
June 17, 2013 |
PCT NO: |
PCT/CA2013/000577 |
371 Date: |
December 23, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61663881 |
Jun 25, 2012 |
|
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|
Current U.S.
Class: |
292/199 |
Current CPC
Class: |
E05B 81/34 20130101;
Y10T 292/1082 20150401; Y10T 292/308 20150401; E05B 79/10 20130101;
E05B 85/243 20130101; Y10T 292/1079 20150401; B60Q 9/00 20130101;
Y10T 292/1047 20150401; E05B 81/06 20130101; E05B 85/26 20130101;
E05B 81/14 20130101 |
International
Class: |
E05B 79/10 20060101
E05B079/10; B60Q 9/00 20060101 B60Q009/00; E05B 85/24 20060101
E05B085/24 |
Claims
1. A vehicle latch, comprising: a ratchet movable between a striker
capture position wherein the ratchet is positioned to retain a
striker and a striker release position wherein the ratchet is
positioned to release the striker, wherein the ratchet is biased
towards the striker release position; a primary pawl movable
between a ratchet holding position wherein the primary pawl is
positioned to hold the ratchet in the striker capture position and
a ratchet release position wherein the primary pawl permits the
movement of the ratchet out of the striker capture position,
wherein the primary pawl is biased towards the ratchet holding
position; an auxiliary ratchet operatively connected to the primary
pawl, wherein the auxiliary ratchet is movable between a primary
pawl enabling position in which the auxiliary ratchet permits the
primary pawl to move to the ratchet holding position and a primary
pawl disabling position in which the auxiliary ratchet positions
the primary pawl in the ratchet release position, wherein the
auxiliary ratchet is biased towards the primary pawl disabling
position; a secondary pawl movable between an auxiliary ratchet
holding position in which the secondary pawl is positioned to hold
the auxiliary ratchet in the primary pawl enabling position, and an
auxiliary ratchet release position in which the secondary pawl is
positioned to permit movement of the auxiliary ratchet to the
primary pawl disabling position, wherein the secondary pawl is
biased towards the auxiliary ratchet holding position; and a gear
that is movable to a secondary pawl locking position in which a
gear locking surface on the gear directly blocks movement of a
secondary pawl locking surface on the secondary pawl so that the
gear directly locks the secondary pawl in the auxiliary ratchet
holding position.
2. A vehicle latch as claimed in claim 1, wherein the gear is
operatively connected to the secondary pawl such that rotation of
the gear to a reset position causes movement of the secondary pawl
to the auxiliary ratchet holding position after the auxiliary pawl
is in the primary pawl enabling position.
3. A vehicle latch as claimed in claim 2, wherein the gear has a
first gear drive surface that is engageable directly with a
secondary pawl drive surface on the secondary pawl and wherein
rotation of the gear to a secondary pawl release position directly
drives the secondary pawl to the auxiliary ratchet release
position.
4. A vehicle latch as claimed in claim 3, wherein the gear has a
second gear drive surface that is engageable directly with an
auxiliary ratchet drive surface on the auxiliary ratchet and
wherein rotation of the gear to a reset position drives the
auxiliary ratchet to the primary pawl enabling position and causes
the secondary pawl to move to the auxiliary ratchet holding
position.
5. A vehicle latch as claimed in claim 4, further comprising a gear
biasing member that biases the gear towards the secondary pawl
locking position from the secondary pawl release position and from
the reset position.
6. A vehicle latch as claimed in claim 5, wherein the secondary
pawl locking position is between the secondary pawl release
position and the reset position.
7. A vehicle latch as claimed in claim 6, further comprising a
reset position sensor positioned to detect the presence of the gear
in the reset position.
8. A vehicle latch as claimed in claim 7, further comprising a
secondary pawl locking position sensor positioned to detect the
presence of the gear in the secondary pawl locking position.
9. A vehicle latch as claimed in claim 8, further comprising a
controller that receives signals from the reset position sensor
that are indicative of whether the gear reaches the reset position,
and wherein the controller is operatively connected to the gear,
wherein the controller is configured to: a) selectively drive the
gear towards the reset position; and b) notify a driver of the
vehicle of a problem in the event that the gear does not reach the
reset position after a selected period of time passes after step a)
is initiated.
10. A vehicle latch as claimed in claim 9, further comprising a
motor, wherein the controller is operatively connected to the motor
and the motor is operatively connected to the gear, wherein the
controller is configured to selectively drive the gear towards the
reset position via the motor.
11. A vehicle latch as claimed in claim 8, further comprising a
controller that receives signals from the secondary pawl locking
position sensor that are indicative of whether the gear reaches the
secondary pawl locking position, and wherein the controller is
operatively connected to the gear, wherein the controller is
configured to: a) selectively cause movement of the gear towards
the secondary pawl locking position; and b) carry out at least one
action in the event that the gear does not reach the secondary pawl
locking position after a selected period of time passes after step
a) is initiated, wherein the at least one action is selected from
the group of actions consisting of: notifying a driver of the
vehicle of a problem with the vehicle latch; and drive the gear
towards the secondary pawl locking position.
12. A vehicle latch as claimed in claim 11, further comprising a
motor, wherein the controller is operatively connected to the motor
and the motor that is operatively connected to the gear, wherein
the controller is configured to selectively cause movement of the
gear towards the secondary pawl locking position by cutting power
to the motor, and to drive the gear towards the secondary pawl by
sending power to the motor.
13. A vehicle latch as claimed in claim 7, wherein the reset
position sensor comprises a Hall effect sensor and wherein a magnet
is positioned on the gear.
14. A vehicle latch, comprising: a ratchet movable between a
striker capture position wherein the ratchet is positioned to
retain a striker and a striker release position wherein the ratchet
is positioned to release the striker, wherein the ratchet is biased
towards the striker release position; a primary pawl movable
between a ratchet holding position wherein the primary pawl is
positioned to hold the ratchet in the striker capture position and
a ratchet release position wherein the primary pawl permits the
movement of the ratchet out of the striker capture position,
wherein the primary pawl is biased towards the ratchet holding
position; an auxiliary ratchet operatively connected to the primary
pawl, wherein the auxiliary ratchet is movable between a primary
pawl enabling position in which the auxiliary ratchet permits the
primary pawl to move to the ratchet holding position and a primary
pawl disabling position in which the auxiliary ratchet positions
the primary pawl in the ratchet release position, wherein the
auxiliary ratchet is biased towards the primary pawl disabling
position; a secondary pawl movable between an auxiliary ratchet
holding position in which the secondary pawl is positioned to hold
the auxiliary ratchet in the primary pawl enabling position, and an
auxiliary ratchet release position, in which the secondary pawl is
positioned to permit movement of the auxiliary ratchet to the
primary pawl disabling position, wherein the secondary pawl is
biased towards the auxiliary ratchet holding position; a gear that
is operatively connected to the secondary pawl, wherein the gear is
rotatable to cause movement of the secondary pawl towards the
auxiliary ratchet holding position and wherein the gear is
rotatable to cause movement of the secondary pawl towards the
auxiliary ratchet release position, wherein the gear is rotatable
to a secondary pawl locking position to lock the secondary pawl in
the auxiliary ratchet holding position, and wherein the gear is
rotatable to a reset position during which the gear causes movement
of the secondary pawl to the auxiliary ratchet holding position
after the auxiliary ratchet has moved to the primary pawl enabling
position; and a reset position sensor positioned to detect the
presence of the gear in the reset position.
15. A vehicle latch as claimed in claim 14, wherein movement of the
gear to the reset position causes movement of the auxiliary ratchet
to the primary pawl enabling position.
16. A vehicle latch as claimed in claim 14, wherein rotation of the
gear to the reset position in which the gear causes movement of the
secondary pawl to the auxiliary ratchet holding position after
causing movement of the auxiliary ratchet to the primary pawl
enabling position.
17. A vehicle latch as claimed in claim 14, further comprising a
controller that receives signals from the reset position sensor
that are indicative of whether the gear reaches the reset position,
and wherein the controller is operatively connected to the gear,
wherein the controller is configured to: a) selectively drive the
gear towards the reset position; and b) notify a driver of the
vehicle of a problem in the event that the gear does not reach the
reset position after a selected period of time passes after step a)
is initiated.
18. A vehicle latch as claimed in claim 17, further comprising a
motor, wherein the controller is operatively connected to the motor
and the motor is operatively connected to the gear, wherein the
controller is configured to selectively drive the gear towards the
reset position via the motor.
19. A vehicle latch as claimed in claim 14, further comprising a
secondary pawl locking position sensor positioned to detect the
presence of the gear in the secondary pawl locking position.
20. A vehicle latch as claimed in claim 19, further comprising a
controller that receives signals from the secondary pawl locking
position sensor that are indicative of whether the gear reaches the
secondary pawl locking position, and wherein the controller is
operatively connected to the gear, wherein the controller is
configured to: a) selectively cause movement of the gear towards
the secondary pawl locking position; and b) carry out at least one
action in the event that the gear does not reach the secondary pawl
locking position after a selected period of time passes after step
a) is initiated, wherein the at least one action is selected from
the group of actions consisting of: notifying a driver of the
vehicle of a problem with the vehicle latch; and driving the gear
towards the secondary pawl locking position.
21. A vehicle latch as claimed in claim 20, further comprising a
motor, wherein the controller is operatively connected to the motor
and the motor that is operatively connected to the gear, wherein
the controller is configured to selectively cause movement of the
gear towards the secondary pawl locking position by cutting power
to the motor, and to drive the gear towards the secondary pawl by
sending power to the motor.
22. A vehicle latch as claimed in claim 14, wherein the reset
position sensor comprises a Hall effect sensor and wherein a magnet
is positioned on the gear.
23. A vehicle latch, comprising: a ratchet movable between a
striker capture position wherein the ratchet is positioned to
retain a striker and a striker release position wherein the ratchet
is positioned to release the striker, wherein the ratchet is biased
towards the striker release position; a pawl movable between a
first position and a second position, wherein when the ratchet is
in the closed position and the pawl is in the first position, the
pawl at least indirectly holds the ratchet in the closed position,
and wherein when the pawl is in the second position, the pawl
permits movement of the ratchet to the open position, wherein the
pawl is biased towards the auxiliary ratchet holding position; and
a gear that is movable to a pawl locking position wherein a gear
locking surface on the gear directly blocks movement of a pawl
locking surface on the pawl so that the gear directly locks the
pawl in the second position.
24. A vehicle latch as claimed in claim 23, wherein the pawl is a
secondary pawl, and wherein the vehicle latch further comprises a
primary pawl and an auxiliary ratchet, wherein the primary pawl is
movable between a ratchet holding position wherein the primary pawl
is positioned to hold the ratchet in the striker capture position
and a ratchet release position wherein the primary pawl permits the
movement of the ratchet out of the striker capture position,
wherein the primary pawl is biased towards the ratchet holding
position, and wherein the auxiliary ratchet is operatively
connected to the primary pawl, wherein the auxiliary ratchet is
movable between a primary pawl enabling position in which the
auxiliary ratchet permits the primary pawl to move to the ratchet
holding position and a primary pawl disabling position in which the
auxiliary ratchet positions the primary pawl in the ratchet release
position, wherein the auxiliary ratchet is biased towards the
primary pawl disabling position, and wherein the first position of
the secondary pawl is an auxiliary ratchet holding position in
which the secondary pawl is positioned to hold the auxiliary
ratchet in the primary pawl enabling position, and wherein the
second position of the secondary pawl is an auxiliary ratchet
release position, in which the secondary pawl is positioned to
permit movement of the auxiliary ratchet to the disabling
position.
25. A vehicle latch, comprising: a housing; a primary ratchet
pivotally mounted to the housing via a primary ratchet pin joint
and movable between a striker capture position wherein the ratchet
is positioned to retain a striker and a striker release position
wherein the ratchet is positioned to release the striker, wherein
the ratchet is biased towards the striker release position; an
auxiliary ratchet pivotally mounted to the housing via an auxiliary
ratchet pin joint; a primary pawl pivotally mounted to the
auxiliary ratchet via a primary pawl pin joint and movable between
a ratchet holding position wherein the primary pawl is positioned
to hold the ratchet in the striker capture position and a ratchet
release position wherein the primary pawl permits the movement of
the ratchet out of the striker capture position, wherein the
primary pawl is biased towards the ratchet holding position,
wherein the auxiliary ratchet is movable between a primary pawl
enabling position in which the auxiliary ratchet permits the
primary pawl to move to the ratchet holding position and a primary
pawl disabling position in which the auxiliary ratchet positions
the primary pawl in the ratchet release position, wherein the
auxiliary ratchet is biased towards the primary pawl disabling
position; a secondary pawl pivotally mounted to the housing via a
secondary pawl pin joint and movable between an auxiliary ratchet
holding position in which the secondary pawl is positioned to hold
the auxiliary ratchet in the primary pawl enabling position, and an
auxiliary ratchet release position in which the secondary pawl is
positioned to permit movement of the auxiliary ratchet to the
primary pawl disabling position, wherein the secondary pawl is
biased towards the auxiliary ratchet holding position; a gear
pivotally mounted to the housing via a gear pin joint for movement
about a gear axis, wherein the gear is movable to a secondary pawl
locking position in which a gear locking surface on the gear
directly blocks movement of a secondary pawl locking surface on the
secondary pawl so that the gear directly locks the secondary pawl
in the auxiliary ratchet holding position.
26. A vehicle latch as claimed in claim 25, wherein the gear has a
first gear drive surface that is engageable directly with a
secondary pawl drive surface on the secondary pawl and wherein
rotation of the gear to a secondary pawl release position directly
drives the secondary pawl to the auxiliary ratchet release
position, and wherein the gear has a second gear drive surface that
is engageable directly with an auxiliary ratchet drive surface on
the auxiliary ratchet and wherein rotation of the gear to a reset
position drives the auxiliary ratchet to the primary pawl enabling
position and causes the secondary pawl to move to the auxiliary
ratchet holding position.
27. A vehicle latch as claimed in claim 26, wherein the latch
further comprises a reset position sensor positioned to detect the
presence of the gear in the reset position; a secondary pawl
locking position sensor positioned to detect the presence of the
gear in the secondary pawl locking position; a motor that is
operatively connected to the gear, and a controller that is
operatively connected to the motor, wherein the controller receives
signals from the reset position sensor that are indicative of
whether the gear reaches the reset position, and signals from the
secondary pawl locking position sensor that are indicative of
whether the gear reaches the secondary pawl locking position,
wherein the controller is configured to: a) selectively operate the
motor to drive the gear towards the reset position; and b) notify a
driver of the vehicle of a problem in the event that the gear does
not reach the reset position after a selected period of time passes
after step a) is initiated, and wherein the controller is
configured to: c) selectively cut power to the motor to cause
movement of the gear towards the secondary pawl locking position;
and d) carry out at least one action in the event that the gear
does not reach the secondary pawl locking position after a selected
period of time passes after step a) is initiated, wherein the at
least one action is selected from the group of actions consisting
of: notifying a driver of the vehicle of a problem with the vehicle
latch; and drive the gear via the motor towards the secondary pawl
locking position.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application U.S. Ser. No. 61/663,881 filed Jun. 25, 2012,
the entire content of which is incorporated herein by
reference.
FIELD
[0002] The disclosure generally relates to the art of vehicle
latches and more specifically vehicle latches that utilize double
pawl arrangements.
BACKGROUND
[0003] Double pawl arrangements are known in the latching art. The
double pawl arrangement may utilize a primary pawl and ratchet
connected to a secondary pawl and ratchet. The connection may be
configured such that only a portion of the forces experienced by
the primary pawl and ratchet are applied to the secondary pawl and
ratchet, thus requiring a relatively low effort to release the
latch. While a low effort to release the latch is desirable, a
problem can occur that an unbalanced force may release the latch in
unintended circumstances such as during a crash event. It would be
desirable to prevent such events.
[0004] In addition, in double pawl arrangements both pawls must be
reset to their locked positions. Biasing means such as springs are
conventionally employed for such purpose. But over time, these
biasing forces may degrade, or may be insufficient occasionally to
cope with other impediments to returning the pawls to their
respective locked positions. An at least partial solution is sought
to such problems.
SUMMARY
[0005] In one aspect a vehicle latch is provided having a ratchet,
a primary pawl, an auxiliary ratchet and a secondary pawl, and
further including a gear that is movable to a secondary pawl
locking position wherein the gear directly blocks movement of the
secondary pawl and locks the secondary pawl in an auxiliary ratchet
holding position to prevent premature or unintended opening of the
latch.
[0006] In an embodiment of the above noted aspect, the ratchet is
movable between a striker capture position wherein the ratchet is
positioned to retain a striker and a striker release position
wherein the ratchet is positioned to release the striker. The
ratchet may be biased towards the striker release position. The
primary pawl is movable between a ratchet holding position wherein
the primary pawl is positioned to hold the ratchet in the striker
capture position and a ratchet release position wherein the primary
pawl permits the movement of the ratchet out of the striker capture
position. The primary pawl may be biased towards the ratchet
holding position. The auxiliary ratchet is operatively connected to
the primary pawl and is movable between a primary pawl enabling
position in which the auxiliary ratchet permits the primary pawl to
move to the ratchet holding position and a primary pawl disabling
position in which the auxiliary ratchet positions the primary pawl
in the ratchet release position. The secondary pawl is movable
between an auxiliary ratchet holding position in which the
secondary pawl is positioned to hold the auxiliary ratchet in the
primary pawl enabling position, and an auxiliary ratchet release
position in which the secondary pawl is positioned to permit
movement of the auxiliary ratchet to the disabling position. The
secondary pawl may be biased towards the auxiliary ratchet holding
position.
[0007] In another aspect, a vehicle latch is provided that includes
a ratchet, a primary pawl, an auxiliary ratchet and a secondary
pawl, and further including a gear that is operatively connected to
the secondary pawl. The gear is rotatable to cause movement of the
secondary pawl towards an auxiliary ratchet holding position and is
rotatable to cause movement of the secondary pawl towards the
auxiliary ratchet release position. The gear is rotatable to a
secondary pawl locking position to lock the secondary pawl in the
auxiliary ratchet holding position. The gear is rotatable to a
reset position during which the gear causes movement of the
secondary pawl to the auxiliary ratchet holding position after the
auxiliary ratchet has moved to the primary pawl enabling position.
In some embodiments the gear causes movement of the auxiliary
ratchet to the primary pawl enabling position. A reset position
sensor is provided and is positioned to detect the presence of the
gear in the reset position.
[0008] In yet another aspect, a vehicle latch is provided,
comprising a ratchet, a pawl and a gear. The ratchet is movable
between a striker capture position wherein the ratchet is
positioned to retain a striker and a striker release position
wherein the ratchet is positioned to release the striker. The
ratchet is biased towards the striker release position. The pawl is
movable between a first position and a second position. When the
ratchet is in the closed position and the pawl is in the first
position, the pawl at least indirectly holds the ratchet in the
closed position. When the pawl is in the second position, the pawl
permits movement of the ratchet to the open position. The gear is
movable to a pawl locking position wherein a gear locking surface
on the gear directly blocks movement of a pawl locking surface on
the pawl so that the gear directly locks the pawl in the second
position. Optionally, the pawl is a secondary pawl and there is a
primary pawl and an auxiliary ratchet provided.
[0009] In yet another aspect, a vehicle latch is provided and
includes a motor, a worm, a gear, a primary ratchet, a primary
pawl, an auxiliary ratchet and a secondary pawl all extend in
planes that are parallel to each other.
[0010] In another embodiment of the above noted aspect, the ratchet
is pivotally mounted to the housing via a primary ratchet pin joint
and is movable between a striker capture position wherein the
ratchet is positioned to retain a striker and a striker release
position wherein the ratchet is positioned to release the striker.
The ratchet may be biased towards the striker release position. The
primary pawl is pivotally mounted to the auxiliary ratchet via a
primary pawl pin joint and is movable between a ratchet holding
position wherein the primary pawl is positioned to hold the ratchet
in the striker capture position and a ratchet release position
wherein the primary pawl permits the movement of the ratchet out of
the striker capture position. The primary pawl may be biased
towards the ratchet holding position. The auxiliary ratchet is
pivotally mounted to the housing via an auxiliary ratchet pin joint
and is operatively connected to the primary pawl and is movable
between a primary pawl enabling position in which the auxiliary
ratchet permits the primary pawl to move to the ratchet holding
position and a primary pawl disabling position in which the
auxiliary ratchet positions the primary pawl in the ratchet release
position. The secondary pawl is pivotally mounted to the housing
via a secondary pawl pin joint and is movable between an auxiliary
ratchet holding position in which the secondary pawl is positioned
to hold the auxiliary ratchet in the primary pawl enabling
position, and an auxiliary ratchet release position in which the
secondary pawl is positioned to permit movement of the auxiliary
ratchet to the disabling position. The secondary pawl may be biased
towards the auxiliary ratchet holding position. The gear is
pivotally mounted to the housing via a gear pin joint.
[0011] In a further embodiment, the gear has a first gear drive
surface that is engageable directly with a secondary pawl drive
surface on the secondary pawl. Rotation of the gear to a secondary
pawl release position directly drives the secondary pawl to the
auxiliary ratchet release position. The gear also has a second gear
drive surface that is engageable directly with an auxiliary ratchet
drive surface on the auxiliary ratchet. Rotation of the gear to a
reset position drives the auxiliary ratchet to the primary pawl
enabling position and causes the secondary pawl to move to the
auxiliary ratchet holding position.
[0012] In a still further embodiment, the latch further comprises a
reset position sensor positioned to detect the presence of the gear
in the reset position, a secondary pawl locking position sensor
positioned to detect the presence of the gear in the secondary pawl
locking position, a motor that is operatively connected to the
gear, and a controller that is operatively connected to the motor.
The controller receives signals from the reset position sensor that
are indicative of whether the gear reaches the reset position, and
signals from the secondary pawl locking position sensor that are
indicative of whether the gear reaches the secondary pawl locking
position. The controller is configured to:
[0013] a) selectively operate the motor to drive the gear towards
the reset position; and
[0014] b) notify a driver of the vehicle of a problem in the event
that the gear does not reach the reset position after a selected
period of time passes after step a) is initiated,
[0015] and is configured to:
[0016] c) selectively cut power to the motor to cause movement of
the gear towards the secondary pawl locking position; and
[0017] d) carry out at least one action in the event that the gear
does not reach the secondary pawl locking position after a selected
period of time passes after step a) is initiated, wherein the at
least one action is selected from the group of actions consisting
of: notifying a driver of the vehicle of a problem with the vehicle
latch; and drive the gear via the motor towards the secondary pawl
locking position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing and other aspects will be more readily
appreciated having reference to the drawings, wherein:
[0019] FIG. 1 is a perspective view of a vehicle having a door,
which has a vehicle latch;
[0020] FIG. 2A is a plan view of the latch shown in FIG. 1 with a
portion of the housing of the latch omitted and in a secondary pawl
locking position;
[0021] FIG. 2B is a plan view of a portion of the latch shown in
FIG. 2A in the secondary pawl locking position;
[0022] FIG. 2C is a plan view of a portion of the latch shown in
FIG. 2A in the secondary pawl locking position;
[0023] FIG. 3 is a view of the latch shown in FIG. 2A illustrating
forces acting on components of the latch;
[0024] FIG. 4 is a plan view of a portion of the latch shown in
FIG. 2A leaving the secondary pawl locking position;
[0025] FIG. 5A is a plan view of the latch shown in FIG. 2A in a
secondary pawl release position;
[0026] FIG. 5B is a plan view of a portion of the latch shown in
FIG. 5A in the secondary pawl release position;
[0027] FIG. 6A is a plan view of the latch shown in FIG. 2A in a
reset position; and
[0028] FIG. 6B is a plan view of a portion of the latch shown in
FIG. 6A in the reset position.
DETAILED DESCRIPTION
[0029] FIG. 1 is a perspective view of a vehicle 10 that includes a
vehicle body 12 and at least one vehicle door 14. The vehicle door
14 includes a latch 20 that is positioned on an edge face 15 and
which is releasably engageable with a striker 28 on the vehicle
body 12 to releasably hold the vehicle door 14 in a closed
position. An outside door handle 17 and an inside door handle 16
are provided for opening the latch 20 (i.e. for releasing the latch
20 from the striker 28) to open the vehicle door 14. An optional
lock knob 18 is shown and provides a visual indication of the lock
state of the latch 20 and may be operable to change the lock state
between an unlocked position and a locked position.
[0030] FIGS. 2A and 2B are front views of the latch 20. The latch
20 includes a housing 22 to which a primary ratchet 24 (which may,
for convenience, be referred to as the ratchet 24) is pivotally
mounted via a primary ratchet pin joint 21 for rotation about a
primary ratchet pivot axis 26 mounted in the housing 22. The
ratchet 24 pivots between a fully closed position wherein the
striker 28 (shown schematically in stippled lines) is captured in a
slot 29 by a hook 30 of the ratchet 24, as shown in FIG. 2A, and an
open position (FIGS. 5A and 5B) wherein the striker 28 is not
trapped by the hook 30 and is free to move out of the slot
presented by the ratchet 24. In the view shown in FIG. 2A the
ratchet 24 rotates clockwise to move from the closed position to
the open position.
[0031] The ratchet 24 is biased towards the open position via a
ratchet biasing member 31. The biasing member 31 may be any
suitable type of biasing member, such as, for example, a torsion
spring. A striker bumper 32 is mounted in the housing 22
(underneath the ratchet 24) to cushion against the striker force of
impact and a ratchet bumper 34 is also mounted about a post 36
provided in the housing 22 to cushion against the ratchet force of
impact.
[0032] An auxiliary ratchet 44 is also pivotally mounted in the
housing 22 via an auxiliary ratchet pin joint 45 for movement about
an auxiliary ratchet pivot axis 46. A primary pawl 47 is pivotally
mounted to the auxiliary ratchet 44 via a primary pawl pin joint 49
for movement about a primary pawl pivot axis 51. The auxiliary
ratchet 44 is movable between a primary pawl enabling position
(FIG. 2A) and a primary pawl disabling position (FIG. 5A). In the
primary pawl enabling position the auxiliary ratchet 44 permits the
primary pawl 47 to move to a ratchet locking position to hold the
ratchet 24 in the closed position, as shown in FIG. 2A. In the
primary pawl disabling position (FIG. 5A) the auxiliary ratchet 44
prevents movement of the primary pawl 47 to the ratchet locking
position, and instead holds the primary pawl 47 in a ratchet
release position, as discussed in greater detail below. In the view
shown in FIG. 2A the auxiliary ratchet 44 rotates clockwise to
reach the primary pawl disabling position.
[0033] The auxiliary ratchet 44 includes a cylindrical bore 48
which receives a cylindrical stub of the primary pawl 47 for
pivotally mounting the primary pawl 47 into the bore 48, thereby
forming pin joint 49 of the auxiliary ratchet 44. This provides a
simple means for mounting the primary pawl 47, which may be formed
from a simple stamped or sintered metal piece.
[0034] The auxiliary ratchet 44 also includes a leg 50 which
optionally, as shown in FIG. 2A, terminates in an anvil 52 having a
check shoulder 54 and a cam lip 56. The auxiliary ratchet 44 may be
encapsulated with an elastomeric material and features an optional
hollow 58 (FIG. 2A) so as to provide an elastically deformable band
60 for contacting and absorbing impact against the ratchet 24. A
variant shown in FIG. 2B does not include the cam lip 56, the band
60 and the hollow 58.
[0035] An auxiliary ratchet biasing member 61 located on the
opposing side of the housing 22 biases the auxiliary ratchet 44 to
the primary pawl disabling position. Only the hub portion of the
auxiliary ratchet biasing member 61 is shown in FIG. 2A, (and is
shown in stippled lines), for simplicity. The biasing member 61 may
include a first tang (not shown) that abuts a capstan of pin 46 and
a second tang which cooperates with a fork (not shown) in the
auxiliary ratchet 44 via a slot (not shown) formed in the housing
22.
[0036] Referring back to FIG. 2A, the primary pawl 47 includes a
check arm 68. In the ratchet locking position the check arm 68
stops the ratchet 24 from opening, as shown in FIG. 2A. In the view
of FIG. 2A the primary pawl 47 rotates clockwise to move to the
ratchet release position.
[0037] The angular sweep of the check arm 68 is limited on one side
by an edge 63 in the auxiliary ratchet 44 and on the other side by
the auxiliary ratchet leg 50. A proboscis bumper 72 formed from an
encapsulation of the primary pawl 47 may be provided to cushion
impact of check arm 68 against the auxiliary ratchet leg 50. An
extension 33 of the striker bumper 32 may be provided to reduce or
cushion impact of check arm 68 against the auxiliary ratchet edge
63.
[0038] The primary pawl 47 is biased towards the ratchet locking
position by a primary pawl biasing member 74 wrapped around a post
76 provided in the anvil 52 of the auxiliary ratchet 44. One tang
(not visible in FIG. 2A) of the biasing member 74 rides against the
auxiliary ratchet leg 50, and another tang 78 abuts the check arm
68 of the primary pawl 47. As the biasing member 74 is mounted to
the auxiliary ratchet 44 rather than the fixed housing 22, the
biasing forces on the primary pawl 47 will not vary appreciably as
the auxiliary ratchet 44 rotates. In embodiments wherein the post
76 is not provided, the biasing member 74 may be provided on the
housing 22 or at some other location on the auxiliary ratchet
44.
[0039] The ratchet 24 features primary and secondary locking
surfaces 80 and 82 that interact with the check arm 68 of the
primary pawl 47. The primary locking surface 80 provides a fully
closed position for the ratchet 24 in which the striker 28 is
securely ensconced in the slot 31 of the ratchet 24 such that the
vehicle door 14 is completely closed and the door seals 83 are
compressed. The secondary locking surface 82 provides a partially
closed and locked position of the ratchet 24 wherein the striker 28
is loosely secured in the slot 31 of the ratchet 24 such that the
vehicle door 14 is locked but not completely closed against the
door seals 83.
[0040] A secondary pawl 84 is pivotally mounted in the housing 22
via a secondary pawl pin joint 85 for movement about a secondary
pawl pivot axis 86 for movement between an auxiliary ratchet
holding position where the secondary pawl 84 holds the auxiliary
ratchet 44 in the primary pawl enabling position, as shown in FIG.
2A, and an auxiliary ratchet release position in which the
secondary pawl 84 permits the auxiliary ratchet 44 to move to the
primary pawl disabling position. In the view shown in FIG. 2A the
secondary pawl 84 rotates counterclockwise to reach the auxiliary
ratchet release position. The secondary pawl 84 includes a hook
shoulder 88 for engaging the auxiliary ratchet check shoulder
54.
[0041] The secondary pawl 84 is biased towards the auxiliary
ratchet holding position by a secondary pawl biasing member 91. The
secondary pawl biasing member 91 may be any suitable type of
biasing member, such as, for example, a torsion spring.
[0042] It will thus be seen from the foregoing that the latch 20
provides an eccentric double pawl arrangement for lowering release
effort. More particularly, as illustrated in FIG. 3, there exists a
force Fs on the ratchet 24 that is a reaction to the seal force
from the door seals 83 when the vehicle door is closed. The force
Fs along with the ratchet bias force presents a moment M1 on the
ratchet 24. The force necessary to move the primary pawl 47 will
thus be related to the coefficient of friction between check arm 68
and ratchet shoulder 38 multiplied by a force approximately X/Y of
Fs, where X is the radial distance between the striker and the
ratchet pivot axis 26 and Y is the distance between the primary
pawl/ratchet contact area and the ratchet pivot point. In practice,
the ratio X/Y could be about 40%. Similarly, the force X/Y*Fs
applied to the primary pawl 68 presents a moment M2 about the
auxiliary ratchet 44. The force necessary to move the secondary
pawl 84 will thus be related to the coefficient of friction between
secondary pawl hook shoulder 88 and auxiliary ratchet check
shoulder 54 multiplied by a force approximately A1/A2 of XN*Fs,
where A1 is the radial distance between the force on the primary
pawl 47 and the auxiliary ratchet pivot axis 46 and A2 is the
radial distance between the secondary pawl/auxiliary ratchet
contact area and the auxiliary ratchet pivot point. In practice,
the ratio A1/A2 can be as low as 10-20%. Thus, a relatively low
release effort may be required to open the latch 20.
[0043] Referring to FIG. 2C, which is a view from the opposite side
of the latch 20 to that which is shown in FIGS. 2A and 2B, the
secondary pawl 84 includes a first locking surface 92 on a
secondary pawl locking projection 93. A second locking surface 94
is on a gear locking projection 95, which is provided on a gear 96.
As shown in FIG. 2C, the gear 96 is rotatably mounted to the
housing 22 via a pin joint 97 for movement about a gear axis 99.
The gear 96 is driven by a worm 98, which is itself driven by a
motor 100. The gear 96 is movable (i.e. rotatable) between a
secondary pawl locking position shown in FIG. 2C in which the
second locking surface 94 directly blocks (or otherwise cooperates
with) the first locking surface 92 to prevent movement of the
secondary pawl 84 out of the auxiliary ratchet holding position,
and a secondary pawl release position shown in FIG. 5B, in which
the second locking surface 94 is out of the way of the first
locking surface 92 and thus permits the secondary pawl 84 to move
to the auxiliary ratchet release position.
[0044] Movement of the gear 96 from the secondary pawl locking
position (FIG. 2C) to the secondary pawl release position (FIG. 5B)
may optionally cause the secondary pawl 84 to move to the auxiliary
ratchet release position. Specifically, the gear 96 may include a
first gear drive surface 101 on a projection 102 that is engageable
with a secondary pawl drive surface 104 on the secondary pawl 84.
When the gear 96 is in the secondary pawl locking position (FIG.
2C), the first gear drive surface 101 may be spaced from the
secondary pawl drive surface 104. As the gear 96 moves from the
secondary pawl locking position the gear 96 first reaches a
secondary pawl unlocking position shown in FIG. 4, in which the
first locking surface 92 moves out of the way of the second locking
surface 94. After the gear 96 reaches the secondary pawl unlocking
position, further rotation of the gear 96 causes the first gear
drive surface 101 to drive the secondary pawl 84 out of the
auxiliary ratchet holding position, until the gear 96 reaches the
secondary pawl release position (FIG. 5B), at which point the first
gear drive surface 101 has driven the secondary pawl 84 to the
auxiliary ratchet release position (against the biasing force of
the secondary pawl biasing member 91). This permits the auxiliary
ratchet 44 to move to the primary pawl disabling position under the
biasing force of the auxiliary ratchet biasing member 61, which in
turn brings the primary pawl 47 to the ratchet release position,
which in turn permits the ratchet 24 to move to the open position.
The seal force Fs from the door seals 83 and the biasing force from
the ratchet biasing member 31 both drive the ratchet 24 to the open
position, thereby releasing the striker 28 and opening the vehicle
door 14.
[0045] The motor 100, which is operatively connected to the gear 96
through the worm 98, may be an electric motor. An electronic
controller shown schematically at 106 may be provided and may be
operatively connected to the motor 100, and may selectively send
power to the motor 100 to selectively drive the motor 100. The
controller 106 may be dedicated to the latch or may be part of some
other controller for the vehicle, such as a central ECU that is
used to control several other functions in the vehicle including,
for example, crash detection.
[0046] The controller 106 may have any suitable structure, and may,
for example, include a processor, memory and may contain code that
permits the controller 106 to control the operation of the motor
100 and to carry out the other functions described herein.
[0047] To sense when the gear 96 has reached the secondary pawl
release position, a limit switch (such as a "door open" switch,
handle switch or both), by sensing a current spike as a result of a
component hitting a hard limit, or by reaching a specified time for
applying power to the motor gear assembly 140. An embodiment
employs a limit switch in conjunction with a timeout to avoid
unnecessary power consumption. When the controller 106 detects that
the gear 96 has reached the secondary pawl release position, the
controller 106 immediately rotates the gear wheel 96 to a reset
position (shown in FIGS. 6A and 6B) to bring the latch 20 to a
reset position to ready the latch 20 to receive and capture the
striker 28 again. To move the gear 96 to the reset position, the
motor 100 drives the gear 96, optionally in the opposite direction
to the direction used to bring the gear 96 to the secondary pawl
release position. Rotation of the gear 96 to the reset position
causes movement of the auxiliary ratchet 44 from the primary pawl
disabling position to the primary pawl enabling position via
engagement of a second gear drive surface 109 with an auxiliary
drive surface 110 on an arm of a reset lever 112 that rotates about
the same axis as the auxiliary ratchet 44 (i.e. axis 45). The reset
lever 112 is engageable with the auxiliary ratchet 44 by way of a
reset lever spring (not shown) that acts between the auxiliary
ratchet 44 and the reset lever 112, thereby providing some amount
of lost motion available between the auxiliary ratchet 44. Thus,
when the gear 96 drives the reset lever 112 (via engagement between
surface 109 and surface 110), the reset lever 112, in turn, drives
the auxiliary ratchet 44 through the reset lever spring. It will be
noted that in FIGS. 2A-6B the housing 22 has been omitted so as to
reveal components that would otherwise be obscured.
[0048] After driving the auxiliary ratchet 44 to the primary pawl
enabling position, further rotation of the gear 96 to the reset
position brings the gear drive surface 104 away from the secondary
pawl 84 thereby permitting the secondary pawl 84 to return to the
auxiliary ratchet holding position so as to capture the auxiliary
ratchet 44 in the primary pawl enabling position. Once the gear 96
has reached the reset position, the controller 106 may stop sending
current to the motor 100. As a result, a centering spring shown at
107 in FIG. 2b that may be provided on a post 108, drives the gear
96 to return to the secondary pawl locking position. In the example
shown in FIG. 2b, the centering spring 107 has a first tang 190a
that engages a first tang receiving wall 191a on the gear 96 and a
second tang 190b that engages a second tang receiving wall 191b on
the gear 96. For greater clarity a centering spring is a spring
that permits movement of an object in either of two opposing
directions away from a rest position, wherein regardless of which
direction the object is moved in, the centering spring urges the
object back towards the rest position.
[0049] As can be seen in FIG. 6A, however, even though the
auxiliary ratchet 44 is in the primary pawl enabling position, the
primary pawl 47 is not in the ratchet locking position; instead the
primary pawl 47 abuts a side edge 114 of the ratchet 24, and not
the primary or secondary locking surfaces 80 and 82 respectively of
the ratchet 24, because the ratchet 24 is itself in the open
position. The side edge 114 is divided into a first side edge
portion 114a that extends between the primary and secondary locking
surfaces 80 and 82, and a second side edge portion 114b that
continues from the secondary locking surface 80 onwards. When the
latch 20 is in the reset position as described above, the latch 20
is ready to receive and capture the striker 28 when the vehicle
door 14 is closed.
[0050] Initially, in the reset position, the primary pawl 47 abuts
the second side edge portion 114b. When the vehicle door 14 is
closed and the striker 28 engages the slot 31 of the ratchet 24,
the striker 28 drives the ratchet 24 to rotate (counterclockwise in
the view shown in FIG. 6A) towards the fully closed position. As
the secondary locking surface 82 sweeps past the primary pawl 47,
the primary pawl biasing member 74 falls into contact with the
first side edge portion 114a (from the biasing force of the biasing
member 74). As the ratchet 24 moves into the fully closed position
and the primary locking surface 80 sweeps past the primary pawl 47
the primary pawl 47 moves into the ratchet locking position to
prevent the ratchet 24 from leaving the closed position. The latch
20 is then in the closed position shown in FIGS. 2A-2C.
[0051] In operation, in the auxiliary ratchet holding position, the
secondary pawl 84 can be subject to an inertia force Fi (see FIG.
3) that may occur, for example, in the event of a vehicle crash.
The force Fi, which does not need to be particularly high given the
low release efforts required to open the latch 20 as discussed
above, will urge the secondary pawl 84 towards the auxiliary
ratchet release position. However, the locking of the secondary
pawl 84 by the locking surface 92 on the gear 96 advantageously
prevents the secondary pawl 84 from pivoting into the auxiliary
ratchet release position during a crash.
[0052] By locking the secondary pawl 84 in the auxiliary ratchet
holding position directly with the gear 96, the use of a separate
lever and spring is avoided. This simplifies the construction,
reduces the cost and increases the reliability of the latch 20
relative to a version of the latch 20 that would include an
additional locking lever and spring.
[0053] Referring to FIG. 6B, structure may be provided to verify
that the gear 96 has reached the reset position. For example, a
first Hall-effect sensor shown at 116 may be provided and may be
positioned (e.g. on the housing 22) for sensing the presence of a
magnet 118 positioned on the gear 96 when the gear 96 reaches the
reset position. The sensor 116 may be referred to as a reset
position sensor and may send signals to the controller 106 that are
indicative of whether the gear 96 is in the reset position. Thus,
when the controller 106 attempts to drive the gear 96 to the reset
position the reset position sensor 116 can send a signal to the
controller 106 to indicate when the gear 96 has reached the reset
position. If, within a selected period of time after sending power
to the motor 100 to drive the gear 96 to the reset position, the
controller 106 does not receive a signal indicating that the gear
96 has reached the reset position the controller 106 may notify the
vehicle driver of a problem with the vehicle latch 20. Notifying
the vehicle driver of a problem with the vehicle latch 20 may, for
example entail sending signals to an ECU in the vehicle.
[0054] In addition to sensing when the gear 96 reaches the reset
position, the latch 20 may be configured to sense when the gear 96
reaches the secondary pawl locking position. For example, the latch
20 may include a second Hall-effect sensor 120 that may be referred
to as a secondary pawl locking position sensor and that is
positioned (e.g. on the housing 22) for sensing the presence of the
magnet 118 when the gear 96 reaches the secondary pawl locking
position. After cutting power to the motor 100 after the gear 96
reaches the reset position, if the controller 106 does not receive
a signal from the second Hall-effect sensor 120 indicating that the
gear 96 has reached the secondary pawl locking position under the
biasing force of the centering spring 107 within a selected period
of time (e.g. a second selected period of time), the controller 106
may send power to the motor 100 to drive the gear 96 to the
secondary pawl locking position. Upon receiving a signal from the
second Hall-effect sensor 120 indicating that the gear 96 has
reached the secondary pawl locking position, the controller 106 may
cut power to the motor 100. If, after a further period of time, the
controller 106 still does not receive a signal indicating that the
gear 96 has reached the secondary pawl locking position, the
controller 106 may notify the vehicle driver or may send a signal
to an ECU in the vehicle indicating that there is a problem with
the latch 20.
[0055] Thus, the controller 106 carries out at least one action in
the event that the gear 96 does not reach the secondary pawl
locking position after a selected period of time passes after the
cutting of power to the motor 100 is initiated. The at least one
action is selected from the group of actions consisting of:
notifying a driver of the vehicle 10 of a problem with the latch;
and sending power to the motor 100 to drive the gear 96 towards the
secondary pawl locking position.
[0056] While the sensors 116 and 120 are shown to be Hall-effect
sensors, they may alternatively be any other suitable kind of
sensor. For example, the sensors 116 and 120 could be limit
switches and the magnet 118 could be replaced by a simple
protrusion on the gear 96 that closes the contacts on one of the
limit switches when the gear 96 reaches the reset or secondary pawl
locking positions. Alternatively, the sensor 116 may be a sensor to
detect a current spike in the current supplied to the motor 100 as
the gear 96 dead-ends at the reset position. In such an embodiment,
structure would be provided to limit one end of the travel of the
gear 96 at the reset position, thereby generating the current spike
in the motor 100.
[0057] While the embodiments shown in the figures include a
ratchet, a primary pawl, an auxiliary ratchet, and a secondary
pawl, it is alternatively possible to provide a different
arrangement. In an aspect, the latch may include a ratchet, similar
to the ratchet 24, a pawl similar to pawl 84 and a gear similar to
gear 96. The ratchet is movable between a striker capture position
wherein the ratchet is positioned to retain a striker and a striker
release position wherein the ratchet is positioned to release the
striker. The ratchet may be biased towards the striker release
position (e.g. by a biasing member similar to biasing member 31).
The pawl is movable between a first position and a second position.
When the ratchet is in the closed position and the pawl is in the
first position, the pawl at least indirectly holds the ratchet in
the closed position, and wherein when the pawl is in the second
position, the pawl permits movement of the ratchet to the open
position. The pawl may be biased towards the first position (e.g.
by a biasing member similar to biasing member 91). The gear is
movable to a pawl locking position wherein a gear locking surface
on the gear directly blocks movement of a pawl locking surface on
the pawl so that the gear directly locks the pawl in the second
position.
[0058] In some embodiments, the pawl is directly engaged with the
ratchet. In other embodiments the pawl may be a secondary pawl, and
the vehicle latch may further include a primary pawl and an
auxiliary ratchet, similar to the arrangement shown in the
figures.
[0059] A feature of some embodiments that can be seen in FIGS. 5a
and 6a in particular, is that the motor 100, the worm 98, the gear
96, the primary ratchet 24, the primary pawl 47, the auxiliary
ratchet 44 and the secondary pawl 84 all extend in planes that are
parallel to each other. As a result, the overall shape of the latch
20 may be thinner than some latches of the prior art. This may be
advantageous in permitting the latch 20 to fit in a vehicle door 14
where space is restricted.
[0060] While the above describes one or more particular
embodiments, it will be appreciated that modifications and
variations may be made to the embodiments described herein without
departing from the proper scope of the claims appended hereto.
* * * * *